Dimming the Lights: 2D Simulations of Deflagrations of Hybrid C/O/Ne White Dwarfs Using FLASH

Journal Article · 11 December 2023 · The Astrophysical Journal

DOI: https://doi.org/10.3847/1538-4357/acf658 · OSTI ID:2229808

Feldman, Catherine  ^[1]; Gutierrez, Nathanael  ^[2]; Eisenberg, Ellis  ^[3]; Willcox, Donald E.  ^[4]; Townsley, Dean M.  ^[5]; Calder, Alan C.  ^[1]

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1. Stony Brook Univ., NY (United States)
2. Georgia Institute of Technology, Atlanta, GA (United States)
3. Yale Univ., New Haven, CT (United States)
4. Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
5. Univ. of Alabama, Tuscaloosa, AL (United States)

The dimmest and most numerous outlier of the Type Ia supernova population, the Type Iax event, is increasingly being found in the results of observational campaigns. There is currently no single accepted model to describe these events. This 2D study explores the viability of modeling Type Iax events as a hybrid C/O/Ne white dwarf progenitor undergoing a deflagration using the multiphysics software FLASH. This hybrid was created using the stellar evolution code MESA, and its C-depleted core and mixed structure have demonstrated lower yields than traditional C/O progenitors in previous deflagration-to-detonation studies. To generate a sample, 30 “realizations” of this simulation were performed, the only difference being the shape of the initial match head used to start the deflagration. Consistent with earlier work, these realizations produce the familiar hot dense bound remnant surrounded by sparse ejecta. Our results indicate that the majority of the star remains unburned (∼70%) and bound (>90%). Our realizations produce total ejecta yields on the order of 10⁻²–10⁻¹M_☉, ejected ⁵⁶Ni yields on the order of 10⁻⁴–10⁻²M_☉, and ejecta kinetic energies on the order of 10⁴⁸–10⁴⁹ erg. Compared to yields inferred from recent observations of the dimmest Type Iax events—SN 2007qd, SN 2008ha, SN 2010ae, SN 2019gsc, SN 2019muj, SN 2020kyg, and SN 2021fcg—our simulation produces comparable ⁵⁶Ni yields but too-small total yields and kinetic energies. Reignition of the remnant is also seen in some realizations.

• Research Organization: Stony Brook Univ., NY (United States)
• Sponsoring Organization: National Science Foundation (NSF); USDOE; USDOE Office of Science (SC), Nuclear Physics (NP)
• Grant/Contract Number: FG02-87ER40317
• OSTI ID: 2229808
• Journal Information: The Astrophysical Journal, Journal Name: The Astrophysical Journal Journal Issue: 2 Vol. 959; ISSN 0004-637X; ISSN 1538-4357
• Publisher: IOP PublishingCopyright Statement
• Country of Publication: United States
• Language: English